(Revised Abstract) DESCRIPTION (provided by applicant): The Synthetic Chemistry Shared Service (SCSS) was established to meet the needs of AZCC members for custom synthesis of chemicals not commercially available. Many AZCC investigations focus on the effects and/or mechanisms of action of organic chemicals as they pertain to cancer biology-causation, prevention, and intervention-and these studies often require custom chemical syntheses that cannot be obtained commercially or are prohibitively expensive. In particular, the costs of commercial custom syntheses for isotopically labeled compounds can restrict or eliminate the use of these valuable tools in some laboratories. The spectroscopic characterization of chemicals of unknown structure is also important in some AZCC investigations, but most research groups lack the instrumentation and expertise to carry out multistep syntheses and characterizations of organic compounds. The Synthetic Chemistry Shared Service is a cost-effective solution to these difficulties, with the following specific objectives: Provides consultation to AZCC investigators regarding problems in chemical synthesis and modification; Provides custom chemical synthesis of unlabeled compounds; Provides custom synthesis of stable isotope or radioisotope labeled compounds; Provides assistance in the spectroscopic characterization of unknown compounds; Provides access to combinatorial synthesis, where applicable; Provides interface with other service units to support drug development efforts underway in the AZCC